Transforming laser technologies
Surrey's Photonics Group has played a pivotal role in understanding and developing compound semiconductors for use in photonic devices. The strained-layer quantum well technology developed by Surrey research is now incorporated in the vast majority of CD, DVD and Blu-ray systems, in telecommunications and the internet and in LEDs for solid-state lighting.
In a quantum well laser, there is an extremely thin layer of semiconducting crystals in which the laser light is generated. In the 1990s, Alf Adams discovered that, if the crystal lattice of this layer was grown in a way which put it under strain, it could be ‘squashed’ into a certain shape, producing a more controlled, concentrated beam of light. This concept was completely counter to laser research at the time, which was directed at focusing the laser, rather than straining it. This solution was much more efficient and powerful than any other laser at the time.
This discovery is now considered to be one of the top ten greatest UK scientific breakthroughs of all time with millions of quantum well lasers manufactured by industry annually. Head of Department, Stephen Sweeney, describes the impact of Adams’ work:
[It] essentially made the digital world we live in possible […] lasers that power the internet, CDs, DVDs, computer mice and supermarket checkouts, to name but a few.
Professor Adams’ blue skies research has led to the creation of many new products and the Surrey team today continue to build on this pioneering work in the field of photovoltaics, working towards more energy efficient solutions to benefit society and the environment.